1. Field of the Invention
The present invention relates generally to wheelchairs for transporting invalids and, more particularly, to a wheelchair having a chair assembly that is shiftable relative to the frame along a generally horizontal path for facilitating transfer of an individual to and from a support surface, such as an automobile passenger seat or a hospital bed.
2. Discussion of Prior Art
Wheelchairs are used in various circumstances to assist with the transport of persons from one location to another. In many instances, the wheelchair serves to transport a person to and from a support surface, such as an automobile passenger seat, a hospital bed, etc. It is, of course, necessary to safely transfer the person from the support surface to the chair, or vice versa. With conventional wheelchair designs, however, the safe transfer of a person to and from the wheelchair is often very difficult. Such transfer is particularly problematic with highly debilitated persons.
A conventional wheelchair typically includes a wheeled frame having a pair of rear drive wheels and a pair of relatively smaller front castor wheels, a chair for supporting a person in a sitting position, and footrests upon which the person places her feet during transport. The chair faces forwardly and is attached to the frame in a position generally between the front and rear wheels for stability purposes. Furthermore, the chair is traditionally surrounded on all but its forward side by a pair of armrests and a chair back, all of which project upwardly from the chair. The footrests traditionally extend forwardly from the frame ahead of the front wheels for supporting the persons feet above the ground during transport. A conventional footrest includes a bar fixed to the frame and a pedal swingably supported on the bar for swinging movement about a substantially horizontal, fore-and-aft axis. Such a configuration allows for swinging of the pedal between a substantially horizontal foot supporting position and an upright position, in which the pedal is swung out of the foot supporting position so that the person's feet may be placed on the ground between the upright pedals during transfer of the person to and from the wheelchair.
Thus, transfer of a person to and from the wheelchair requires that the person be moved in a generally fore-and-aft direction into and out of a sitting position. For example, to transfer a person from a support surface to the wheelchair, the wheelchair is placed in close proximity to the support surface and the pedals are swung to the upright position. Subsequently, the person raises from a recumbent position on the support surface to her feet and walks, in most cases with assistance, to the wheelchair. The person is positioned relative to the wheelchair so that her legs and feet are between the upright pedals and bars of the footrests and her backside faces the chair. The person is finally lowered to a sitting position on the chair and the pedals are swung to a foot supporting position. Of course, transfer of a person from the wheelchair to a support surface is essentially the reverse of the steps set forth above.
The conventional wheelchair design, as hereinabove described, is highly problematic, particularly with regard to transfer of the patient to and from the wheelchair. As evident from the description, the person must step between the footrests when being transferred to and from the wheelchair. This can indeed be very difficult and unsafe for persons who are not highly agile. Furthermore, some wheelchair configurations have the front wheels positioned forwardly of the frame so that the person must also maneuver between the front wheels when being transferred to and from the wheelchair.
Conventional wheelchairs are also problematic in the sense that most wheelchair constructions prevent placement of the chair adjacent the support surface, whereby the person can simply slide from the support surface to the chair, or vice versa. That is, the wheelchair components extending forwardly beyond the chair prevent the unobstructed forward side of the chair from being placed alongside the support surface, such that transfer of a person to and from the wheelchair necessarily involves raising the person to her feet and moving the person between the footrests.
It will be appreciated that conventional footrests also present an obstacle for care providers that assist the person. Of course, the care provider, along with the person, must avoid tripping over the footrests during transfer. Moreover, in instances where it is desired to place the wheelchair as near the support surface as possible so as to minimize movement of the person, the support surface, chair and footrests define an essentially enclosed area that prevents optimum location of the care provider immediately behind or in front of the person during transfer. The location of the wheelchair relative to a support surface, and the access to the person during transfer to and from the wheelchair afforded the care provider are attributes of the wheelchair which supplant, rather than supplement, one another. That is proximity of the chair relative to the support surface must be sacrificed in favor of unobstructed access to the person, and vice versa. For example, a person demanding a significant amount of assistance requires that the wheel chair be spaced sufficiently away from the support surface to provide the care provider with the access to assist the person. However, because of the necessary spacing of the wheelchair from the support surface for accommodating the care provider, the person must move a greater distance during transfer to and from the wheelchair.